Squirrels do not hibernate, but they do prepare for the cold winter. Tree squirrels will rest in the winter, saving energy and focusing on eating and sleeping. Winter rest is not the same as hibernation. Resting is a milder form of dormancy where animals will do the same activities they usually do, just not as often.
In order to understand if squirrels hibernate, one must understand what exactly hibernation is.
Hibernation is when certain mammals reduce their metabolic activity and their body temperature as a way to adapt to winter weather. A hibernating animal spends most of the winter season in a death-like state. If you saw an animal hibernating, you may think it was dead.
Hibernators reserve body fat, may store food, and use a protective den. Every several weeks during hibernation, the animal will awaken. This will raise its body temperature and heart rate.
During its awakened state, the animal will stretch and move around. It will also eat before returning to its hibernating state, also known as torpor. Hibernating is similar to being in a coma.
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Do squirrels hibernate?
Squirrels use their internal photo-neuroendocrine system to know when winter is coming because it allows them to feel the length of days changing.
In the fall, they will start preparing for winter. Squirrels will eat more than usual in the fall to gain weight for the upcoming cold season. This weight gain will help them stay warm in the cold weather, and this fat can be used as energy when available food supplies are low.
Once the temperature drops, squirrels will grow a winter coat. The more fur it grows, the darker it appears. This dark fur will retain heat from the sun to help warm the squirrel.
Squirrels will prepare their nests, also called dreys, by scatter-hoarding, when they will place nuts, seeds, berries, bones, and insects around their nests to eat during the winter. They will bury these foods in different locations so that another hungry animal won’t eat it all in one dig.
Squirrels have been noted to be intelligent creatures because they remember where they buried their food. During the daytime in winter, squirrels will emerge from their nests in the trees to eat their food.
However, sometimes squirrels will sleep for a few days at a time during their winter rest. Squirrels will rest for about twenty hours each day during the winter months.
What about gray or red squirrels?
Gray and red squirrels are tree squirrels that rest in the winter but don’t hibernate.
Gray squirrels will make nests in trees and may nest in your home. Gray squirrels may rest in attics and walls of houses.
Red squirrels tend to sleep in tree cavities more than gray squirrels. They also prefer to nest in thick evergreen trees. Gray squirrels enjoy nesting alone, but sometimes they will share their nest.
Both gray and red squirrels will scatter hoard, although red squirrels are known to be more forgetful and sometimes can’t remember where they hid their food.
Both types of squirrels will put on weight for the winter. In the fall, red squirrels put on about twelve percent of their body mass, while a gray squirrel puts on about twenty-five percent of its body mass.
A red squirrel will grow a gray winter coat, causing people to mistake it for a gray squirrel.
Do ground squirrels hibernate?
Ground squirrels are the only type of squirrels that hibernate.
The ground squirrel’s body mechanism is different from other squirrels, and because of this different make-up, ground squirrels are the only squirrels that even can hibernate.
This animal’s metabolism can slow without killing the squirrel. These types of squirrels can survive without eating, drinking, or excreting.
Ground squirrels hibernate for about five to eight months. They come out of hibernation in late spring, around March.
Ground squirrels hibernate in underground burrows that they have created. These hibernating squirrels create extensive burrows with plenty of room to store food, hibernate, and care for their young.
Ground squirrels live in colonies, so when they hibernate, they hibernate together.
The burrows that they make can be damaging to surrounding structures. Their tunnels can cause damage to sidewalks, fencing, tree roots, and more.
Ground squirrels may emerge from hibernation on warmer days and scour for food near homeowners’ properties. The squirrels will be a nuisance when they dig through garbage cans, sheds, and barns.
The Arctic Ground squirrel lives in Alaska and also hibernates. They can survive body temperatures below freezing during hibernation.
Do squirrels hibernate in any US state?
Some US states, such as California, don’t get cold enough for ground squirrels to need to hibernate. Some ground squirrels in warmer US states can be active throughout the year.
In areas where there is no snow in the winter, squirrels tend not to hibernate. Whether a ground squirrel hibernates or not depends on the weather conditions of an area.
In late summer, squirrels in warm regions will even go into summer estivation, similar to hibernation, only in the summer. This is when the high heat is unbearable for them, just as when the freezing cold is severe.